A microelectronic package assembly, a method for disconnecting a microelectronic package from a lead frame, and a method for manufacturing a microelectronic package assembly are known from JP 11-330335 A.
Generally, microelectronic package assemblies are manufactured during industrial mass production of semiconductor chips. Such a microelectronic assembly comprises a lead frame containing a plurality of microelectronic packages. Each microelectronic package generally comprises a semiconductor chip arranged on a substrate, which may be a structural part of the lead frame initially, which both are overmoulded by an encapsulation. The microelectronic packages are connected to the lead frame via holding bars for securing the packages against unintentional movements and via contact leads for electrically connecting the chips of the microelectronic packages to external electronics. The contact leads may also be a structural part of the lead frame initially. After manufacturing the microelectronic assembly, the electronics of the microelectronic packages are tested. For this purpose, the contact leads are disconnected from the lead frame in a punching step. At the same step also the substrate holding the semiconductor chip may be fully or partially disconnected from the lead frame. Subsequently a package singulation step takes place either at the manufacturer or at the costumer in order to provide individual microelectronic packages for further use in electronic devices. During this singulation step, the holding bars of the lead frame are disconnected from the microelectronic packages by e.g. breaking the holding bars away from the package body. The most commonly used singulation process, however, is a separate punching step.
The microelectronic package assembly known from JP 11-330335 A comprises a lead frame and a plurality of encapsulated microelectronic packages which are connected to one another via holding bars. The holding bars are inserted into slits of the package bodies such that the holding bars and the package bodies are engaged to one another. In order to disconnect the packages from the lead frame, the holding bars are receded from the package body using an engagement releasing tool comprising a tapered terminal part. During release, the tapered terminal part is moved in a direction perpendicular to a longitudinal axis of the holding bars such that elastically deformable parts of the holding bars are bent away from the package and the ending part of the holding bars are moved in a direction reverse to the insertion direction. Thus, the microelectronic packages are disconnected from the lead frame.
However, the known methods of disconnecting a microelectronic package may be complex and may lead to a low yield since damages may occur during the singulation step.